Sorter control to prevent over-stacking in the sorter trays

ABSTRACT

An improved reproduction system incorporating a processor for making copies, a document handler for automatically feeding in seriatim documents to be copied to the processor and thereafter returning the documents to the document supply tray for either removal or recycling, and a sorter for either stacking or collating the copies, the sorter including a procession of copy receiving trays. To prevent overfilling of the sorter trays beyond their individual capacity, the system incorporates a control effective when the reproduction system is operated in the stacking mode to automatically switch over to the next sorter tray when the capacity of the preceding sorter tray is reached, and so on as necessary. Following completion of the copy program for the document then being copied, copies of the next succeeding document will be routed to the next empty sorter tray.

alem [191 Acquaviva et al.

Nov. 5, 1974 SORTER CONTROL TO PREVENT OVER-STACKING IN THE SORTER TRAYS Xerox Corporation, Stamford, Conn.

Filed: Dec. 4, 1972 Appl. No.: 312,251

Assignee:

[56] References Cited UNITED STATES PATENTS 2/1971 Snellman 271/64 UX 2/1972 Schulz et a1. r 271/64 X 8/1972 Deutsch 271/64 X OTHER PUBLICATIONS Hellman, .1. L. Progressive Stacking Mechanism. IBM Technical Disclosure Bulletin Vol. 13, No. 10,

78 U"fillllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllEE 55 9' lllllllllllllllltlllllllllmfg Int. Cl B65h 29/58 gilllllllllllllllllllllllllllllllllllllmllllllllllllllllll ifo l-l llll| v v.01. .m, in. n .us, A

l .i' Mllllllllllllllllllllll pp. 3060-3061. Man, 1971.

Primary ExaminerRiehard A. Schacher Assistant Examiner-Bruce H. Stoner, Jr.

[57] ABSTRACT An improved reproduction system incorporating a processor for making copies. a document handler for automatically feeding in seriatim documents to be copied to the processor and thereafter returning the documents to the document supply tray for either removal or recycling, and a sorter for either stacking or collating the copies, the sorter including a procession of copy receiving trays. To prevent overfilling of the sorter trays beyond their individual capacity, the system incorporates a control effective when the reproduction system is operated in the stacking mode to automatically switch over to the next sorter tray when the capacity of the preceding sorter tray is reached, 'and so on as necessary. Following completion of the copy program for the document then being copied, copies of the next succeeding document will be routed to the next empty sorter tray.

2 Claims, 4 Drawing Figures llllllllllllllllll -l3/ SORTER CONTROL TO PREVENT OVER-STACKING IN THE SORTER TRAYS This invention relates to a reproduction system, and more particularly, to an improved reproduction system incorporating means to prevent overfeeding of copies to any one tray of the reproduction system output sorter.

ln reproduction systems incorporating both a high speed copy processor and copy sorter, the processor could be programmed to make copies in excess of the capacity of the individual sorter trays. In this event, unless some precaution is taken, a jam may occur in the sorter when these excess copies attempt to enter the already filled copy tray. Visual observation by the operator cannot always be relied upon to protect against this situation, particularly as processing speeds become higher and higher. Additionally, more modern systems may provide an automatic document handler for supplying the documents to be copied. This may result in the operator being present only long enough to initially set up and program the system. Should the copy number programmed be in excess of the individual copy tray capacity, a serious jam may occur while the system is unattended.

It is a principal object of the present invention to provide a new and improved reproduction system.

It is a further object of the present invention to provide a reproduction system incorporating means to prevent overfilling of the copy trays of the system sorter.

It is an object of the present invention to provide a control for a reproduction system adapted when the tray capacity of the system sorter is reached to automatically switch to the next empty tray.

It is an object of the present invention to provide means to prevent overfilling of the sorter paper trays by switching from a filled tray to the next empty tray, and when copies of the next succeeding document are received to route such copies into the next succeeding tray.

It is a further object of the present invention to provide a control adapted to direct the first copies of each original into the first open tray of a sorter.

This invention relates to a reproduction system, comprising in combination; a processor for making copies of original documents; a sorter for sorting the copies into desired orientation, the sorter having a procession of copy receiving trays; and control means adapted to automatically switch to the next succeeding sorter tray when the number of copies in the tray equals the copy storage capacity of the sorter tray.

These and other objects of the invention will be apparent from the ensuing description and drawings in which:

FIG. 1 is a perspective view of the reproduction system incorporating the improved control of the present invention;

F IG. 2 is a side sectional view showing details of the processor platen cover and transport;

FIG. 3 is a side sectional view of the reproduction system sorter; and

FIG. 4 is a diagram showing schematically the control circuit for the reproduction system of FIG. 1 including the sorter control of the present invention.

For a general understanding of reproduction apparatus with which the present invention may be incorporated, reference is made to F IG. 1 wherein various components of a typical electrostatic printer system are illustrated. The printer system is of the xerographic type and is generally designated with the reference numeral 10. As in all xerographic systems, a light image of an original to be reproduced is projected onto the sensitized surface of a xerographic plate to form an electrostatic latent image. Thereafter, the latent image is developed with toner material to form a xerographic powder image corresponding to the latent image on the plate surface. The powder image is then electrostatically transferred to a record material such as a sheet or web of paper or the like to which it may be fused by a fusing device whereby the powder image is caused permanently to adhere to the surface of the record material.

The xerographic processor indicated by the reference numeral 11 is arranged as a self-contained unit having all of its processing stations located in a unitary enclosure or cabinet. The printer system includes an exposure station at which a light radiation pattern of a document to be reproduced and positioned on a glass platen 12 is projected onto a photoconductive surface in the form of a xerographic belt 13. The document is transported by a recirculating document handler 15 from supply stack 17 on tray 19 to the platen for exposure and then returned to the supply stack on completion of the exposure. This procedure is repeated until the entire stack has been copied at which time the cycle may be repeated or the documents removed.

As best seen in F IG. 2, document handler 15 includes a belt-type platen transport 14 disposed atop platen 12 for moving documents into and out of copying position on platen 12.-Transport 14 is operatively supported on spaced rollers 16, 16', roller 16 being driven by suitable means (not shown) to operate transport 14 forward and backward as required. The entire transport 14 is swingable about the axis of rear drive roller to permit transport 14 to be raised for access to platen l2. Similarly, platen cover 9, which overlays transport 14, is supported for swinging movement about the axis of pin 18 to permit cover 9 to be swung open. This is normally done when it is desired to copy documents manually and to provide service accessibility to the parts.

Suitable illumination means such as flash lamps 18 are provided. The light image is projected by first mirror 20, projection lens 21, and second mirror 23 onto the xerographic belt 13 at the focal plane for the lens 21 at a position indicated by the dotted line 25.

As an interface structure and for unobstructive optical projections, the.side of the cabinet is formed with an enlarged rectangular opening to permit the projection of image light rays from the lens 21 to the mirror 23. Similarly, the cabinet forming the document plane is formed with a corresponding rectangular opening that mates with the opening in the printer cabinet when the two cabinets are operatively joined together for copying purposes. Suitable light tight gaskets may be utilized adjacent the exterior of each opening in the cabinets in order to minimize the leakage of unwanted extraneous light.

The xerographic belt 13 is mounted for movement around three parallel arranged rollers 27 suitably mounted in the frame processor 11. Belt 13 is driven by a suitable motor (not shown) at an appropriate speed. The exposure of the belt to the light image from the document selectively discharges the photoconductive layer to provide an electrostatic latent image corresponding to the light image projected from the document.

Movement of belt 13 takes the electrostatic latent image past developer apparatus 29 where the electrostatic latent image is developed by a suitable toner in conformance with the charge pattern thereon. After development, the powder image moves to an image transfer station whereat record material, i.e., paper or sheets from either main or auxiliary sheet supply 30, 31, respectively, is brought into image transfer relationship with belt 13 to receive the powder image therefrom. Suitable roll type feeder devices 33 are provided for feeding one sheet at a time from supply stacks 30, 31, the sheet being moved in synchronism with belt 13 during transfer of the developed image and registered with the image on belt 13 by suitable means (not shown).

After transfer, sheets are conveyed to a suitable fuser 32 which fuses or fixes the powder thereon. After fusing, the sheets may be deposited in either copy tray 35 or conveyed to sorter 32, a suitable gate (not shown) being provided to selectively route the sheets to either tray 35 or sorter 32.

Further details of the processing devices and stations in the printer system may be found in US. Pat. Nos. 3,661,452, issued May 9, I972, and 3,597,071, issued July 27, 1971, which are commonly assigned with the present invention.

Referring to FIG. 3, sorter 32 comprises a base frame 51 which supports upper and lower sorter bins 53, 55, respectively. Lower bin 55 includes a unitary framework which defines a series of trays 59 which receive copy sheets in a downward direction. Similarly, upper bin 53 has a unitary framework which defines a series of trays 59 for receiving copy sheets.

Sheets enter sorter 32 through an opening formed in the frame of the lower sorting assembly 55. The sheets pass through guides 63 to a pair of pinch rolls 65 and 67 which direct the sheets to either horizontal transport 69 or to vertical transport 129 depending on the position of a deflector 135. Transport 69 is made up of a plurality of horizontal belts 71 driven by motor 153 (FIG. 4). Belts 71 are above the sheet path and free wheeling rollers 73 are positioned below the sheet path. Above rollers 73 are rollers 74 which are positioned within belts 71 and are spring loaded downward to ensure proper traction between the belts and sheets being transported.

Sheets traveling on the horizontal belts 71 are deflected downward into an appropriate tray by fingers or gates 76. The position of each gate is controlled by an individual solenoid 37 in accordance with the solenoid control logic (FIG. 4). As will appear, operation of solenoids 37 is normally controlled by the passage of a sheet downwardly from horizontal transport 69 into one ofthe trays 59 which causes the breaking and making of the light beam established between light source 78 and a suitable optical sensor such as phototransistor 80. The ensuing signal pulse is relied upon to trigger the next gate solenoid while de-energizing the previous gate solenoid. This results in the gate for the next tray 59 being moved into intercepting position, that is depressed. while the gate to the preceding tray is moved out of intercepting position, that is raised, suitable spring means (not shown) being provided to bias gates 76 in a raised position.

The upper sorting bin 53 includes a similar horizontal transport 117 driven by a motor 167 which moves above the sheet path and free wheeling rollers 119 positioned below the sheet path. Above rollers 119 are rollers 121 which are positioned within belts 117 to ensure proper traction as in the case of rollers 74. Gates 123 are provided for each of the trays in upper bin 53, individual solenoids 37 being provided to operate each gate 123 in the same manner as described for gates 76 of lower bin 55. A suitable light and phototransistor combination 125, 127 is provided in bin 53.

As will appear, the system operator may elect to use or not use sorter 32 and/or document handler 15. Where sorter 32 is not used, copies are stacked in processor tray 35. Where sorter 32 is used, the operator may program the system 10 to provide either stacked or collated copy output by actuating the selector S1 or $2, respectively, on control panel 6. Where it is desired to use the document handler 15, either alone or in combination with sorter 32, selector S3 or S4 is actuated, selector S3 programming document handler 15 for automatic operation, selector S4 for single document feed. By depressing suitable ones of the switch button S5 the number of copies desired for each document is selected.

Whenever sorter selector S1 or S2 is actuated, the sorter logic 301 (FIG. 4) interrogates sensors 303 and 305 to determine whether or not copies, normally from a previous job, are in any of the trays 59 of bins 53, 55. On a signal from either sensor 303 or 305, logic 301 precludes input of copies to the bin 53, 55 affected. This is done by switching deflector 135 to the appropriate position. Should both sorter bins 53, 55 have copies therewithin, the joint signals to logic 311 precludes operation of the system 10 until such time as one or both of the bins 53, 55 are cleared.

Sensors 303, 305, which are suitable phototransistors similar to sensors and 127 described earlier, are located in lower and upper sorter bins 55 and 53, respectively FIG. 3). Suitable lamps 306, 307 are provided therefor. Illumination from the lamps 306, 307 will be sensed by sensors 303 and 305 when no sheet material is present in the sorter trays. If either or both of the bins are empty, the signal from the sorter logic 301 enables operation of processor 11.

Print selector S6 controls start up of the printer system 10. Where either of selectors S3 or S4 is actuated, document'handler 15 will feed the first document from tray 17 to platen 12 of processor 11. With the first document in position, the signal from the document handler logic 313 enables processor 11 to start copying, the resulting copies being deposited in either tray 35 of processor 11 or in sorter 32 if one of the sorter selectors S1 or $2 has been actuated.

When sorter 32 is used, where both bins 53, 55 are empty, deflector is in the position shown in FIG. 3. Copies are therefore routed into lower bin 55 for stacking in trays 59 thereof, starting with tray 59.

In processor 11, an exposure counter 309 counts flashes of flash lamps 18. It should be understood that the exposure counter could be used with a scan type exposure system as well.

It will be appreciated that phototransistors 80, 127 count the copies entering the trays, the signals from one of phototransistors 80, 127 being fed via OR circuit 302 to copy counter 415 which may comprise any suitable counting device and which in cooperation with logic 301 controls the position of tray deflectors 76, 123 as will appear. ln addition, logic 301 controls starting and stopping of the individual sorter bin motors 153, 167, as well as the position of bin deflector 135.

The signal output of copy counter 415 controls selectively through sorter logic 301 the appropriate solenoid matrix circuits 427, 429 for sorter bins 53, 55. Matrix circuits 427, 429 control operation of the bin deflector solenoids 37 to raise and lower the individual fingers 76, 123, respectively. Sorter logic 301 includes a suitable comparison circuit (not shown) which serves to compare the number of copies programmed with the number of copies delivered as recorded by copy counter 415.

Printer system may be programmed for a collated copy output with multiple document feed by actuating selectors S2 and S3. During system operation in this mode, sorter logic 301 steps the solenoid matrix circuit 427 or 429 for the sorter section 53 or 55 then in use from a starting position, wherein the first copy produced is routed into the first sorter tray 59, through a series of steps equal to the number of copies programmed or the total tray capacity of the sorter bin, whichever is less, in'accordance with the copy program. Whenever the total number of copies programmed or the sorter tray capacity is reached by processor 11, the signal from counter 309 to processor logic 311 stops the processor 11 while actuating document handler 15 to remove the document on platen l2 and bring up the next succeeding document. Following this, operation of processor 11 resumes.

In the meantime, as the last copy of the document previously on platen 12 is deposited in the appropriate sorter tray, the signal from copy counter 415 causes sorter logic 301 to reset the deflector control matrix 327 or 329 for the sorter section then in use so that the first copy of the new document is directed into the first tray of the sorter bin.

The above process continues until the number of copies programmed is reached or until the last document in the document handler tray 17 is processed. Where the copy cycle is completed, a signal from counters 309, 415 cycles out the reproduction system 10. However, where the last document is copied and the program is not finished, the copy cycle is automatically repeated. In this circumstance document handler functions to refeed the first document from document tray 17 to platen 12 of processor 11 in preparation for resumption of the copying process.

However, before processor 11 can commence operation, the signal input from the appropriate detector 303 or 305 to sorter logic 301 reflecting the presence of copies in the sorter bin just used, is responded to by sorter logic 301 which actuates deflector 135 to route the next batch of copies into the other empty sorter bin. The copy cycle then continues, the copies generated by processor 11 being deposited in the trays of the other sorter bin until either the program is completed, at which point the system cycles out, or the copy capacity of the bin then in use is reached. In this latter case, following copying of the last document. the document handler 15 again recycles the documents to bring the first document into position on platen 12. At this point, the signal input from the detector 303 or 305 of the sorter section last used will be responded to by the sorter logic 301 which will switch deflector gate 135 so as to route the next batch of copies into the other sorter section if that sorter section is empty. If the other sorter section has not been cleared of copies, and no other empty sorter section is available, the signals from both detectors 303, 305 to sorter logic 301 inhibits further operation of the printer system 10 until such time as at least one of the sorter bins is empty.

lt is understood that the reproduction system 10 may be operated in a stack mode wherein the copies of each document produced by processor 11 are stacked together in the various trays of sorter 32 starting with the first tray 59 of whichever bin 53 or 55 is in use. In this mode of operation one document at a time is positioned on platen 12, either automatically by document handler 15 or manually by the operator, the latter through the expediency of raising the document transport assembly 14 and cover 9 to expose platen 12, placing the document thereon, and then reclosing the transport and cover. It is understood that processor logic control 311 is programmed for the number of copies to be made by actuating appropriate ones of the switches S5. At the same time, selector S1 is actuated to set the sorter logic 301 to stack mode and selector S4 is actuated to set document handler logic 313 to single feed mode if document handler 15 is to be used.

In this mode of operation, when the total number of copies programmed for the document being copied is reached, as indicated by counter 309, processor 11 cycles out and the document on platen 12 is removed by document handler 15. When the last copy therefor enters the first tray 59 of the sorter bin 53 or 55 in use, the signal from copy counter 415 to sorter logic 301 actuates the appropriate matrix circuit 427, 429 to depress the finger for the next succeeding sorter tray. The system is accordingly ready to process the next document in tray 17. Processor 11 may then be restarted to copy the second document in accordance with the previously established program.

The aforedescribed process continues until all the original documents have been copied, the copies of each document being stacked in successive ones of the sorter trays. If, during the program, copies are stacked in the last tray of the bin being used, the signal from the appropriate bin detector 303, 305 to logic 301 switches bin deflector to thereafter direct copies into the other empty bin.

As will be understood, the sorter trays of sorter 32 have a limited sheet storage capacity. To protect against overfilling of an individual sorter tray, a suitable counter circuit 500 is provided, circuit 500 serving to identify the copy storage capacity of the individual sorter trays 59. Circuit 500, which may be preset at the factory for a predetermined number of copy sheets, may include suitable adjusting means (not shown) to enable the setting thereof to be changed in the field to accommodate different types or weights of paper.

The output of circuit 500 is fed to a suitable comparator circuit 501 having a second input from copy counter 415. The output of comparator circuit 501 is gezd to sorter logic 301 controlling bin matrixes 427,

Enabling of circuit 500 may be controlled by sorter logic 301 in response to actuation of sorter stack selector S1. Circuit 500 is not normally required when sorter collating selector S2 is actuated where the capacity of document handler 15 does not exceed the copy capacity of the individual sorter trays 59. [n this circumstance, as will be understood, the number of copies made when collating cannot exceed the copy capacity of the individual sorter trays. Where, however, the document handler 15 can handle a number of documents in excess of the capacity of the individual sorter trays, counter circuit 500 may be arranged to be enabled whenever sorter 32 is used.

During operation of reproduction system 10 in the stacking mode, effected by actuating selector S1, with or without actuation of selector S4 depending on whether or not it is desired to feed the documents automatically by document handler or manually through the expediency of raising platen cover 9 and transport 14, when the number of copies fed to the tray in use equals the predetermined tray capacity as determined by circuit 500, comparison circuit 501 is triggered. The other signal from circuit 501 to logic circuit 301 actuates the matrix circuit 427, 429 for the sorter bin 53 or 55 in use to release the finger 76, 123 for the tray then in use and depress the finger for the next sorter tray. Succeeding copies of the program are therefore routed into the next sorter tray. 1f the capacity of the next tray is insufficient, circuit 500 will respond again when the capacity of the tray is reached to cause logic 301 to step to the next sorter tray, and so forth and so on until the program is completed.

On completion of the copy program for the document then on platen 12, the signal from copy counter 415 to sorter logic 301 switches to the next succeeding empty sorter tray or bin as the case may be and copies ofthe next document enter the next succeeding tray or bin.

It will be understood that counter circuit 500 and comparison circuit 501 may be replaced by individual sheet detectors in each of the sorter trays adapted to generate a signal whenever the number of sheets in the tray reach a predetermined number. In this circumstance the signal would be fed directly to sorter logic tions or changes as may come within the scope of the following claims.

What is claimed is:

1. In a reproduction system the combination of:

a processor for making copies of a plurality of original documents in succession;

a sorter for sorting said copies into desired orientation, saidsorter having a procession of copy receiving trays; and,

control means responsive to the individual copy capacity of said sorter trays to automatically switch to the next succeeding sorter tray when the number of copies produced of one of said original documents exceeds the storage capacity of one or more individual sorter trays, said control means being adapted to control the operation of the sorter to automatically deliver copies of the succeeding document into the next succeeding empty sorter tray at the commencement of stacking of the copies of said succeeding document.

2. In a document copying system operative in a copy stacking mode to produce copies, said system including a processor for making copies, a document handler for automatically bringing a succession of documents to be copied into copying relationship with said processor, and a sorter for receiving copies made by said processor, said sorter having a procession of copy receiving trays, the combination of:

control means for automatically switching copies from one tray to the next empty tray when the copy capacity of said one tray is reached whereby to prevent overfilling of said trays, said control means automatically switching from one tray to the next tray for commencing the placement of copies of the succeeding document in the next empty tray irrespective of the number of copies in the preceding tray to prevent inter-mingling of copies from each document being copied; and,

means adapted when said system is in said stacking mode to actuate said control means to proceed from one empty tray to the next in progression. 

1. In a reproduction system the combination of: a processor for making copies of a plurality of original documents in succession; a sorter for sorting said copies into desired orientation, said sorter having a procession of copy receiving trays; and, control means responsive to the individual copy capacity of said sorter trays to automatically switch to the next succeeding sorter tray when the number of copies produced of one of said original documents exceeds the storage capacity of one or more individual sorter trays, said control means being adapted to control the operation of the sorter to automatically deliver copies of the succeeding document into the next succeeding empty sorter tray at the commencement of stacking of the copies of said succeeding document.
 2. In a document copying system operative in a copy stacking mode to produce copies, said system including a processor for making copies, a document handler for automatically bringing a succession of documents to be copied into copying relationship with said processor, and a sorter for receiving copies made by said processor, said sorter having a procession of copy receiving trays, the combination of: control means for automatically switching copies from one tray to the next empty tray when the copy capacity of said one tray is reached whereby to prevent overfilling of said trays, said control means automatically switching from one tray to the next tray for commencing the placement of copies of the succeeding document in the next empty tray irrespective of the number of copies in the preceding tray to prevent inter-mingling of copies from each document being copied; and, means adapted when said system is in said stacking mode to actuate said control means to proceed from one empty tray to the next in progression. 